CFD 및 GT-Power 해석을 이용한 가솔린 Dual-Injector 엔진의 성능 개선에 관한 연구

Optimal intake system design for a dual-injector PFI (Port Fuel Injection) application was studied by using CFD analysis and the performance improvement was predicted by GT-Power analysis. Dual-injector PFI system provides better charge cooling and combustion stability which makes it possible to achieve engine performance and fuel efficiency improvement on conventional MPFI system. Since fuel injection system change from a conventional PFI to a dual-injector system was tried in this study, intake manifold and ports designs also should be changed to incorporate the dual-injector system and to maximize the performance and fuel efficiency gain. A number of intake port design variants were evaluated by using CFD from tumble and flow capacity perspectives and the intake manifold design was proposed to fit the selected port design. As intake system design was decided, engine performance simulation was carried out to project engine performance improvement with dual-injector based engine hardware. From the series of development activities, dyno test showed engine torque increase especially at low engine speeds and BSFC improvement at key part load conditions.